Remediation of contaminated water, such as hydrocarbon-contaminated groundwater which is the subject of an environmental clean-up project, can be achieved with an air stripper system, including a vertical stripping tower, installed temporarily at the site. The contaminated water is introduced to the top of the tower and caused to flow downwardly by force of gravity, while stripper air is introduced from the bottom of the tower and caused to flow upward. The mixing of water and air that occurs during this countercurrent flow results in the transfer of the contaminants from the water to the airstream. Relatively clean water collects at the bottom of the tower which can be re-used, e.g., re-introduced to the ground. The contaminated airstream exits the top of the tower and is typically treated to remove the contaminants prior to emission of the air to the atmosphere. The degree to which the contaminants are removed from the water is dependent upon tactors such as the height of the stripper tower and the volume of stripper air passed through the tower. In general, an increase in decontamination effectiveness is achieved by increasing tower height and air flow volume. The economics of such remediation and the difficulties of maintenance of units at remote locations are of important concern, as are esthetics in many instances.